Temperature senders for OMC V-4 cross-flow

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petryshyn

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Hi guys, is there a preferred location to install 2 temp. senders(one for each bank) on a 86 OMC V-4 crossflow?<br /> :confused:
 
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csmithrc

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Re: Temperature senders for OMC V-4 cross-flow

Hi schematic. I just put a Faria temp gauge on a 77 Evinrude. I put an toggle switch under the dash so i could switch between cylinders.I used a temp sender on each cyl head bolt.It runs at about 140 degrees F. unless sitting and idleing then it will go just a little higher.Hope this helps some. :)
 
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petryshyn

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Re: Temperature senders for OMC V-4 cross-flow

Thanks csmithrc: Thats exactly what I had in mind. I'm converting a water level gauge($4.00 US) to read temperature and will switch from left to right bank as well. Where did you get the senders and how much?<br /><br />Thanx<br /> :)
 
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evin300

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Re: Temperature senders for OMC V-4 cross-flow

I have considered adding a temp sender. Also, If both senders are of equal make, why couldnt you run them together in (series) on a single gauge with no switch? <br /><br />On my set up, I have the temp sender on the starboard head and the overheat warning horns (switches) on the port and starboard, so both heads are bieng measured. <br /><br />It would be nice If I could get a warning horn switch for the port head that would close sooner, say 160-170 deg instead of 200, then I would not feel as compelled to have a second temp sender for the port head.<br /><br />Shematic, I had a removeable plug on my (1989 V-8) starboard head to install the OMC sender, but I cant remember if there is one on the port.<br /><br />PS Factory overheat alarms are run in series.
 
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petryshyn

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Re: Temperature senders for OMC V-4 cross-flow

Hi evin300!! <br /> All this talk of temperature and its freezing up here!!!!<br /> The sender for a temp. gauge is a variable resistor of a specific value. It completes the ground circuit for an electromagnetic gauge(balancing coil gauge). It varies the current through a coil according to its temperature. If you put them in series, it would just compound the resistance and increase the gauge reading.<br /> Each sender must have its own gauge to control. Thats why we want to switch each sender in or out of the circuit, thus checking each bank.<br /> I like your idea of having a temp. switch that closes at a lower temp. I'll look into it and see if I can find a temp. switch that'll do this. I remember seeing some adjustable ones.<br /> What I want to do is mount the senders in a blind hole(one that doesn't make it through to water) I believe there were some engines that had extra blind holes drilled and tapped. Since I can't find any yet, looks like I'll have to drill a couple. I don't like the idea of using a 'L' bracket and a external sender because I feel the readings will be influenced by the ambient temp. under the hood. I don't like the idea of having a sender in the water jacket, as electrolysis may eat the sender over time.<br /> I am looking for some cheap senders. Don't care what application. I've modified the gauge so it calibratable. When all the dust settles, and I've worked the bugs out, I'll post you and give you the results...if your interested??<br /> :)
 
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Dunk

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Re: Temperature senders for OMC V-4 cross-flow

schematic, try looking at http://egauges.com/ <br /><br /> I was looking for VDO gauges that that site came up using Yahoo. They have senders, but you'll need to pay attention the OHM's and match it the gauge head you are using.<br /><br /> I've got 87 110hp Rude and there's no where on it to put a sender in the block. The looper engines had the threaded hole back then. My 90 225 had one. You'll need to find those "s" or "z" shaped brackets like you mentioned. Don't worry about ambient temps under the hood. The heads will always be warmer. When I install sender using the brackets I first sand/grind the tip of the sender flat so it makes good contact with the head. Using one of the water jacket bolts to mount it with. I also like to remove the paint on the head under the sender. Once its mounted just repaint the small spot.<br /><br /> I had dual senders like you are talking and used a 3 position push pull switch to switch back and forth.
 
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evin300

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Re: Temperature senders for OMC V-4 cross-flow

Cool, I will be interested to hear how it works out. Ya I have the threaded holes that arent exposed to water, the external mount would be hard to insulate I agree. <br /><br />On the idea a switching manually, how about a voltage actuated relay, to where one bank is normally closed, and if the other "blind" bank hits a certain voltage (temp) the relay will activate and show the temp on that bank.<br /><br />I set up a relay to use my single trim gauge for both trim and jack hieght, normally closed reads trim angle. When I go to adjust engine height the gauge reads for that untill I let go of the switch. I am happy with it, but there is quite a bit of needle bounce when first activated. Maybe a liquid filled gauge or some kind of supressor?
 
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petryshyn

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Re: Temperature senders for OMC V-4 cross-flow

evin300, Is it cold down there??????? <br />I like your way of thinking!!<br />-first off, for your dual trim gauge bounce, I'd recommend putting an electrolytic capacitor from 's' to ground. Start low like 10uf or so and work your way up until bounce diminishes. Don't go too too high as it will slow down the gauge reaction time.<br />-secondly, yes it would actually be easy to build an automatic switching module that would sense the highest temp and connect that sender. The same unit could also easily turn a light on the dash showing which bank. I'd use a comparitor chip costing all of about $2.00 US. A little supportive circuitry and your off....Gotta be a hobbyist though....or a HVAC Tech....LoL...You'll do juuuuuuuusssssssst fine!! <br /> ;) ;)
 
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csmithrc

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Re: Temperature senders for OMC V-4 cross-flow

Schematic I got the gauge at the Shad Connection and you can get an extra sender for about $9.I did as Dunk said and clean off the spot on the head and sender to get a good connection.I didn't think i had it good and flat against the head but the sender holder part is aluminum and it transfers the heat really well.Good luck with your project.....
 
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petryshyn

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Re: Temperature senders for OMC V-4 cross-flow

Thanks for the info Dunk, pretty nice website. Prices are good too.<br /><br />Thanks csmithrc, found Shad Connection lots of good stuff, and again good prices...<br /><br />I gotta see if either are in Canada. The darn exchange kills us....<br />
2fish.gif
 
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csmithrc

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Re: Temperature senders for OMC V-4 cross-flow

The part number is 90405 in case you have not found it yet.I have ordered several times from them and they ship quick.Good luck. :)
 
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evin300

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Re: Temperature senders for OMC V-4 cross-flow

Hi schematic, It was pretty warm here today, but tomorrow its supposed to get cool and nasty. How cold up there?<br /><br />Thanks for the good advice! I would rather try that than buy a gauge that wont match the others. <br /><br />That comparitor chip sounds like the hot ticket! You could even have the light under the dash as you probably wouldnt have to reference it often. <br /><br />Again, thanks schematic, I will let ya know how it works out, (wont be for a few months)and let me know how yours works out, I will be anxious to see the Schematic! LOL :)
 
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